Every accepted paper gets a poster session. At a physical conference these take place in a large room(s) that are needed to hold the number of poster boards required. We typically use double-sided boards with 3ft between each board and 25ft between the rows.
Depending on the number of posters, there may be one or two sessions per day, the General Chair will determine the schedule. For in person, food and beverages are served in or near the poster sessions to draw the attendees in. In some cases, the Sponsor Hall is also near by with food and drinks, again to draw the attendees to their booths. Virtual conferences use Gathertown and Topia to mimic in person poster session rooms. Topia is also utilized for sponsor booths. If short talks are given at the poster session, SlidesLive will send links out to the presenters; the posters need to be in the database for SlidesLive to pull from.
If you are an author and wish to change your poster session see self service poster session selection.